How do I unsubscribe?

My following account will  soon be due for renewal;;-
(order number removed)
Start date-5 August 2019
Expire date-20  August 2020
As 85 year old I have struggled for several hours to unsubscribe this without success.
Please…is there anybody out there who can help?
Murray Cameron

Hi Murray,

We request you not to share the order number on a public forum.
We have sent an email and explained the status of your subscription.
Please revert to our email without changing its subject.
Thank you.

Hi Murray,

We request you not to share the order number on a public forum.
We have sent an email and explained the status of your subscription.
Please revert to our email without changing its subject.
Thank you.